It was reported that the first deceased by HIV-infection in the world was found in Africa in 1950, and in an instant, the HIV-infected persons spread all over the world. Recently, it has been reported that a great number of persons were infected with HIV and deceased.
The therapeutic agents for the HIV-infected persons include AZT, ddI, ddC, interleukin-II, GL0223, DHCA, γ-beta-ser Interferon, alpha interferon, gamma interferon, etc.
However, these therapeutic agents have problems of serious side effects or poor efficacy, and any inhibitor or HIV activity (i.e., HIV activity inhibitor) with special efficacy has not been found yet.
On that account, the present inventor has earnestly studied to pursue an inhibitor which inhibits viral activity of Hepatitis B virus and HIV, is able to destroy said viruses and is almost free from anxiety of side effects. As a result, he has found that a specific mycelium extract prepared by a specific process inhibits the Hepatitis B and HIV activity and restrains proliferation of said virus, and he has accomplished the present invention.
Japanese Patent Publication No. 23826/1985 describes a process for preparing a healthful drink comprising the steps of inoculating Lentinus edodes fungus in a solid culture medium comprising bagasse, then untying (disentangling) the solid culture medium containing the proliferated mycelium in such a manner that the amount of the disentangled medium of 12-in mesh would be not more than 30% by weight, adding water and at least one enzyme selected from a group consisting of cellulase, protease and glucosidase to the disentangled solid culture medium with keeping the solid culture medium at 30 to 50° C., grinding and milling the solid culture medium in the presence of the enzyme so that the amount of the bagasse fibers of 12-in mesh is at least 70% by weight, then heating to a temperature of not higher than 95° C. to inactivate the enzyme and sterilize, and filtering the resultant suspension.
Further, Japanese Patent Applications No. 5355/1984 and No. 5356/1984 (i.e., Japanese Patent Publications No. 35149/1992 and No. 6171/1992, respectively) describe processes for preparing healthful drinks using Fomes japonicus fungus.
In these publications, however, there is neither description nor suggestion on that the obtained healthful drinks are effective as inhibitors against Hepatitis B virus or HIV activity.
With respect to physiologically active substances obtained from Lentinus edodes (Japanese edible mushroom, shiitake), some literatures have reported.
In “BIOTHERAPY,” Vol. 2, No. 3, pp. 509-521 (June, 1988), Tetsuo Taguchi et al. state that lentinan obtained from Lentinus edodes inhibits proliferation of HIV by the use thereof in combination with the HIV therapeutic agent AZT. Further, in “Pharmaceutical Magazine,” Vol. 108, No. 3, pp. 171-186 (1988), Kureo Chihara, who is a co-writer of the above thesis, reports that the main substance of polysaccharides obtained from Lentinus edodes is β-1,6:β-1,3-D-glucan.
Furthermore, in “BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS,” Vol. 160, No. 1, pp. 367-373 (1989), Harumi Suzuki et al. report that an extract of Lentinus edodes mycelium (LEM) has anti-HIV effect, and it is describe in “Agri. Biol. Chem.,” Vol 54, No. 2, pp. 479-487 (1990) that the main substance of said extract is a water-soluble lignin contained in the LEM.
By the way, the inhibitor of HIV activity of the present invention exhibits sufficient inhibitory effect against the HIV activity in a concentration of 125 μg/ml in vitro even when it is in the unpurified state, and differs from the above-mentioned substances already reported. The activity against Hepatitis B virus is similar, and the inhibitor is also useful in treating liver cancer.